Nicholas Anelka’s 48th minute strike was enough to see off a strong Porto side at a rain soaked Stamford Bridge.
The Frenchman’s tidy finish ensured The Blues’ quest to claim their first Champions League got off to the best possible start.
It was a lively opening at the Bridge, with Porto front man Hulk looking threatening, forcing a Petr Cech to save with his legs, and Frank Lampard drawing two good saves out of Helton in the first 7 minutes
The second chance should’ve been buried by the Chelsea vice-captain, who was totally unmarked when he met Branislav Ivanovic’s cross, but could only place it at the keeper.
The early zip was taken out of the game by an injury to skipper John Terry, after he was caught by a stray elbow from Porto’s captain Bruno Alves.
The home side continued to apply pressure once the game got back underway but Porto remained resilient, and when Michael Essien thrashed a shot into The Shed it looked as if frustrations might get the better of The Blues.
Up to this point the passing had not been as fluid as normal, with Essien uncharacteristically guilty throughout the night of giving the ball away cheaply in the middle of the park.
Anelka and Lampard both had chances just past the 20 minute mark, the Frenchmen unable to put a convincing near post finish onto Ivanovic’s cross, before Lampard headed wide from Malouda.
Suddenly the visitors snapped into life, with their occasional but dangerous counterattacks quickly becoming spells of pressure.
The impressive Fredy Guarin headed onto the roof of the net in their best chance of the half.
As Porto pressed it was Chelsea’s turn to play on the counter, and a great interception and run by Ricardo Carvalho, Florent Malouda fired over, before neat build up saw Saloman Kalou denied by a last ditch tackle from Rolando right on half time.
Carlo Ancelotti’s team talk had the desired effect, as just 3 minutes after the restart The Blues were in front.
Kalou controlled Nicholas Anelka’s flick on, but the Ivorian couldn’t force a way through and lost possession, but his persistence paid off as he managed to poke the ball through to Anelka, whose initial effort was well saved by Helton before the Frenchmen clipped home the rebound.
It was a smart finish from Anelka under pressure from defenders, and a message sent out that Chelsea don’t have to rely on the suspended Didier Drogba for goals this season.
This proved to be the home side’s best spell of the game, as they quickly went in search of a second that would kill the game. Ivanovic headed just over from a corner, and Florent Malouda was unlucky to see his near post header slap into the side netting with Helton stranded.
Kalou then wasted the clearest chance, the Ivorian forcing a fine save out of the Porto keeper, having found himself unmarked from another Ivanovic cut back.
Porto coach Jesulado Ferreira sensed his side needed a change, and the introduction of Silvestre Varela helped his side push on in the last 20 minutes.
The substitutes first action was to brilliantly deny Ashley Cole a carbon copy of his strike against Burnley.
Cech then twice denied Guarin before Hulk’s run saw him only find the side netting.
It was a nervy finish for The Blues, but tension was eased when Porto winger Fernando picked up his second yellow card for a late challenge on Ashley Cole.
So a winning start for Chelsea and Carlo Ancelotti, and with Athletico Madrid and APOEL drawing in Spain, The Blues are already in a familiar position, on top.
Chelsea: Cech, Ivanovic, Terry, Carvalho, Cole, Essien, Ballack, Lampard, Malouda, Kalou (Belletti 77), Anelka.
Subs not used: Turnbull, Hutchinson, Bruma, J Cole, Sturridge, Borini
Porto: Helton, Alves, Fucile, Rolando, Meireles, Guarin, Rodriguez (Varela 64), Gonzalez (Falcao 54), Perrerira, Fernando, Hulk.
Subs not used: Nuno, Maicon, Sapunaru, Belluschi, Costa.
Man of the Match: Nicholas Anelka